In 1507 cartographers in Europe, struggling to redraw their map of the world to accommodate new discoveries, decided on a name for the western hemisphere. They called it ‘America’ after Amerigo Vespucci, a Florentine explorer who was obscure at the time and has remained so ever since. Quibbles about whether he deserved to have America named after him have dominated the literature. But Amerigo the man – his life, his mind, his character, his relationships, his ambitions and inhibitions- has never inspired a serious, critical biography. Until now.